Packaging



July 7, 1964 l. 5. DE WOSKIN PACKAGING 4 Sheets-Sheet 1 Original Filed May 18, 1959 July 7, 1964 l. s. DE WOSKIN PACKAGING 4 Sheets-Sheet 3 Original Filed May 18, 1959 FIG. I2.

W X, J1. 60006 J y 7, 1964 I. s. DE WOSKIN PACKAGING 4 Sheets-Sheet 4' Original Filed May 18, 1959 ANN United States Patent 3,139,712 PACKAGING Irvin S. De Woskin, St. Louis, Mo., assignor to Beltx Corporation, St. Louis, Mo., a corporation of Missouri Original application May 18, 1959, Ser. No. 813,874, new Patent No. 3,030,752, dated Apr. 24, 1962. Divided and this application May 29, 1961, Ser. No. 113,355

Claims. (Cl. 53-33) This invention relates to packaging, and more particularly to a method of so-called skin packaging of an article in which the article is packaged on a card sealed under a transparent film thereby providing a display package.

This application is a division of my copending application Serial No. 813,874, filed May 18, 1959, entitled Packaging, now U.S. Patent 3,030,752, which is a continuationin-part of my application Serial No. 746,892, filed July 7, 1958, entitled Packaging, now abandoned.

Among the several objects of this invention may be noted the provision of a method of skin-packaging of articles adapted for economical production in quantity of skin packages; the provision of such a method for the production of skin packages in which an article is packaged on a card sealed under a transparent film with the film stretched taut over the article; and the provision of a method such as described which enables heat sealing (and more particularly electronic sealing) of the film to the card all around the article without separation of the stretched film fused during the sealing operation. Other objects and features will be in part apparent and in part pointed out hereinafter.

. The invention accordingly comprises the methods heremafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

FIG. 1 is a perspective view of a skin package made by the method of this invention;

FIG. 2 is a perspective view of a cardboard blank constltuting part of the package;

FIG. 3 is a perspective view in section on line 3-3 of FIG. 1;

FIG. 4 is a perspective view in section on line 4-4 of FIG. 1;

FIG. 5 is a plan view of an apparatus for performing the method of this invention, the apparatus being broken away in the center, and showing certain jigs employed in the operation of the apparatus;

FIG. 6 is a vertical section taken on line 6-6 of FIG. 5;

FIG. 7 is a plan view of a jig per se, the jig being shown in its closed condition;

FIG. 8 is a side elevation of FIG. 7;

FIG. 9 is a plan view of the jig as it appears when open;

FIG. 10 is a side elevation of FIG. 9;

FIG. 11 is an enlarged vertical section taken on line 11-11 of FIG. 9, showing a cardboard blank in the jig, a plastic film associated with the blank, and an article on the film;

FIG. 12 is a view similar to FIG. 11 showing the jig closed;

FIG. 13 is an enlarged vertical section taken on line 13-13 of FIG. 10;

FIG. 14 is an enlarged horizontal section taken on line 14-14 of FIG. 6, the plane of this section being immediately below the bottom surface of a table of the apparatus;

FIG. 15 is an enlarged vertical section taken on line 15-15 of FIG. 14; and

FIG. 16 is a wiring and piping diagram.

3,l39,7l2 Patented July 7, 1964 Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Referring to the drawings, a skin package 1 such as may be produced by the method of this invention is illustrated in FIGS. 1, 3 and 4. It comprises a thin cardboard blank 3 (see FIG. 2) of rectangular shape folded in half on a transverse fold line 5. The portion of the blank on one side of the fold line 5 is designated 7, and the portion on the other side of the fold line is designated 9. Portion 9 constitutes a flap joined to card 7 along fold 5. It has arectangular cut-out 11 constituting what may be termed a window, and itself constitutes: what may be termed a picture frame. The blank 3 has a coating 13 on the surface thereof which is on the inside when the blank is folded of an electronically heat-scalable synthetic plas tic, such as vinyl resin (polyvinyl chloride, for example). The blank 3 may bear printing on the surface thereof which is on the outside when the blank is folded (on the outside of both the card 7 and the flap or frame 9). Card 7 has a hole 15 adjacent the fold line 5 and the flap or frame 9 has a hole 17 adjacent the fold line. These holes register when the blank 3 is folded.

In the completed package, an article A is sealed between the card 7 and a cover 19 of flexible transparent electronically heat-scalable plastic film, such as a vinvyl resin film (a polyvinyl chloride film, for example). This cover is of rectangular shape having a width corresponding to the width of the card 7 (and the flap or frame 9) and height somewhat less than the height of the card (and the frame). It is stretched taut like a skin (hence the name skin package) over the article A, having its margin heat-sealed to the coating 13 on the card 7. Accordingly, the article is hermetically sealed under the cover on the card. The flap or frame 9 overlies the margin of the cover 19 and is electronically heat-sealed to the cover all the way around the margin of the cover, this sealing occurring between the cover and coating on the under surface of the flap or frame 9. The lower edge 19a of the cover is generally coincident with the lower end of the card (and the frame 9) and the upper end 1% of the cover lies below the holes 15, 17 so that the holes are unblocked and available for hanging the package on a pin or peg on a display rack (not shown). The cover 19 is bulged out through the window opening in the frame, and, since the cover is transparent, the article A is visible through the cover, appearing as if it were in a picture frame.

Now referring to FIGS. 5 and 6 of the drawings, a packaging apparatus for carrying out the method of this invention is shown to comprise a relatively long narrow table 21 provided with means for guiding a first series S1 of jigs 23 for movement in one direction (toward the left as viewed in FIG. 5) lengthwise of the table along a first line at one side of the table, and means for guiding a second series S2 of jigs 23 for movement in the opposite direction (toward the right. as viewed in FIG. 5) lengthwise of the table along a second line parallel to the first line at the other side of the table. The guiding means is shown to comprise a center rail 25 extending lengthwise of the table located centrally as regards the width of the table, a rail 27 extending lengthwise of the table at one side of the table, and a rail 29 extending lengthwise of the table at the other side of the table. Rails 25 and 27 in conjunction with the table top define a guideway G1 for the first series S1 of jigs 23. Rails 25 and 29 in conjunction with the table top define a guideway G2 for the second series S2 of jigs 23.

The jigs 23 are all identical. Referring to FIGS. 7-13, a jig 23 is shown to comprise a flat rectangular metal base 31. On the base 31 toward one end thereof (which is referred to as the front end) is an open rectangular metal electrode generally designated 33. The sides of this electrode, each designated 35, are flush with the sides of the base. One end of the electrode, designated 37, is flush with the front end of the base. The other (rear) end of the electrode is designated 39. The electrode bounds a rectangular pocket or recess 41 closed at the bottom by the base 31. A layer 43 of resilient material such as felt may be provided in the bottom of recess 41. The top surfaces of the ends and sides of the electrode 33 are relatively broad flat surfaces and are flush with one another. As herein illustrated, a pin 45 of electrically nonconductive material projects up from the inner end member 39 of the electrode, being centrally located in relation to the length of member 39, and pins 47 of electrically nonconductive material project up from the outer end member 37 of the electrode. Pins 47 are notched as indicated at 49 on the sides thereof facing inward toward recess 41 immediately adjacent the top surface of member 37.

Extending up from the base 31 at the sides thereof and rearward of the electrode 33 are electrically nonconductive blocks 51. These support an electrically nonconductive shaft 53 extending transversely across the base 31 and above the base. Shaft 53 serves pivotally to support a fiat metal clamping plate 55, this plate having electrically nonconductive blocks 57 secured to the underside "thereof having openings 59 receiving the shaft 53. Blocks 57 are located on the inside of blocks 51 and are spaced apart for accommodation of a coil spring 61 therebetween on the shaft 53. The ends of the spring have sleeves 63 and 65 of electrical insulation thereon engaging the base 31 and the underside of plate 55, and the spring acts as a torsion spring tending to bias the plate 55 to swing upward away from the base 31.

Plate 55 carries an upper electrode 67 of open rectangular form somewhat larger than recess 41 on the bottom thereof and toward the free (front) end thereof. The plate 55 is narrower than the base 31 and the sides of the upper electrode 67, each designated 69, are flush with the sides of the plate 55. The outer end 71 of the upper electrode 67 is flush with the outer end of the plate 55. The inner end of the upper electrode is designated 73. The sides and ends of the upper electrode 67 are relatively thin, and their bottom edges are flush with one another. Upper electrode 67 is so dimensioned and positioned relative to the lower electrode 33 that When plate 55 is swung down against the bias of spring 61 to a horizontal position, the lower edges of sides 69 of upper electrode 67 extend along the top surfaces of the sides 35 of lower electrode 33, the lower edge of end member 71 of upper electrode 67 extends along the top surface of end member 37 of lower electrode 33 inside of pins 47, and the lower edge of end member 73 of upper electrode 67 extends along the top surface of end member 39 of lower electrode 33 inside of the pin 45 (see FIG. 8).

Means is provided for releasably holding the clamping plate 55 in its lowered horizontal clamping position against the bias of spring 61. As shown, this means comprises a clamping lever 77 pivoted at one end thereof as indicated at 79 between a pair of brackets 81 mounted on an electrically nonconductive block 83 secured on base 31 at its rear end. At its free end, clamping lever '77 carries a screw 85, the head 87 of which is engageable with the outside of clamping plate 55. Screw 85 is adjustable relative to lever 77, extending through a hole in the end of lever 77 and having nuts 93 threaded thereon on opposite sides of the end of the lever. A toggle lever 95 is pivoted at 97 between the brackets 81, pivot 97 being rearward of and above pivot 79. A pair of toggle links 99 connects the toggle lever 95 and the clamping lever 77. The arrangement is such that by swinging the toggle lever 95 downward, the clamping lever 77 is swung downward. Screw 85 engages the clamping plate 55 and swings it downward. When the plate 55 reaches its horizontal position, the toggle links 99 overcenter,

and clamping lever 77 then acts to hold the clamping plate 55 down in clamping position relative to electrode 33 on base 31. To release the plate 55, toggle lever is swung up to break the toggle, and then spring 61 can swing the plate 55 up.

A toggle-breaking lever 101 is pivoted intermediate its ends at 103 on the outside of one of the brackets 81. At one end (the forward end) of lever 101 is a finger 105 engageable with the knee of the toggle upon clockwise swinging of lever 101 as viewed in FIG. 8 to break the toggle. The other (rearward) end of lever 101 is twisted as indicated at 107 to provide a broad end portion for engagement by an actuating member to be described later. The toggle-breaking lever 101 is lightly biased by a spring 169 to swing clockwise as viewed in FIG. 8 to engage the knee of the toggle, the bias being insufficient to break the toggle.

A plurality of jigs 23 constituting the series S1 are disposed side-by-side in a row in guideway G1 with their rear ends against the center rail 25 and their forward ends against rail 27 (see FIGS. 5 and 6). A plurality of jigs 23 constituting the series S2 are disposed side-by-side in a row in guideway G2 with their rear ends against rail 29 and their front ends against the center rail 25. The center rail 25 terminates short of the ends of rails 27 and 29. The first series S1 of jigs 23 is adapted to be moved forward toward the left end of the table as viewed in FIG. 5 along the line of guideway G1 by a pusher P1. The second series S2 of jigs 23 is adapted to be moved toward the right end of the table as viewed in FIG. 5 along the line of guideway G2 by a pusher P2. Each pusher P1 and P2 is mounted on a post 111 (see FIG. 15) extending up through a longitudinal slot 113 in the table from a slide 115 (see FIGS. 14 and 15 guided for sliding movement longitudinally of the table underneath the table by a guide 117. Pushers P1 and P2 are operable in unison by an air cylinder 119 mounted underneath the table. The piston 121- of cylinder 119 is connected as indicated at 123 to a lever 125 pivoted at 127 underneath the table, and links 129 are provided connecting the ends of the lever to the slides 115. The arrangement is such that on a forward stroke of the piston 121 (movement of the piston from the left and to the right end of cylinder 119 as viewed in FIG. 14), the pushers P1 and P2 are both moved inward from the outer limits of their stroke, and on a return stroke of the piston, the pushers are both moved outward. Each pusher is engageable with the trailing end of the respective series S1 or S2 to push the entire series forward (toward the left as regards series S1, toward the right as regards series S2), each series sliding on the table in its respective guideway G1 or G2. As herein shown, the

movement of the piston 121 is such as to efiect advance of the respective series a distance corresponding to twice the width of a jig 23 on a forward stroke of the piston.

Series S1 of jigs 23, when moved forward (toward the left) by pusher P1, advances to a position wherein the jig at the leading end (the left end) of the series engages a stop 131 on the table at the left end of the table as viewed in FIG. 5. Series S2, when moved forward (toward the right) by pusher P2, advances to a position wherein the jig at the leading end (the right end) of the series engages a stop 133 on the table at the right end of the table as viewed in FIG. 5. The center rail 25 terminates short of each of stops 131 and 133 by a distance somewhat greater than twice the width of a jig. This leaves spaces between the ends of the center rail 25 and the stops 131 and 133 for lateral transfer of two jigs from the leading end of series S1, after advance thereof against stop 131, into position at the trailing end of series S2, and for lateral transfer of two jigs from the leading end of series S2, after advance thereof against stop 133, into position at the trailing end of series S1. The transfer of jigs from the leading end of series S1 to the trailing end of series S2 is effected by a pusher P3,. and the transfer of jigs from the leading end of series S2 to the trailing end of series S1 is effected by a pusher P4. Each pusher P3 and P4 is wide enough to engage the ends of two jigs, and is mounted on a post 135 (see FIG. 15) extending up through a transverse slot 137 in the table from a slide 139 guided for sliding movement transversely of the table underneath the table by a guide 141. Pushers P3 and P4 are operable in unison by an air cylinder 143 mounted underneath the table. The piston 145 of cylinder 143 has cable connections as indicated at 147 to the slides 139. The arrangement is such that on a forward stroke of the piston 145 (movement of the piston from right to left as viewed in FIG. 5), the cables 147 are pulled to move the pushers P3 and P4 through a forward stroke to effect the transfer of jigs. Return of the pushers P3 and P4 to retracted position is effected by spring return means such as indicated at 149 in FIG. 15.

At 151 is indicated an electronic heat-sealing press, having a flat bed 153 and a pneumatically operated head 155 vertically movable toward and away from the bed.

Such presses are well known, essentially comprising a RF. generator for converting a low frequency electric power supply to high frequency electrical energy, this high frequency energy being applied to the bed 153 and head 155 to establish an electrostatic field, the polarity of which is alternated millions of times per second, thereby to accomplish sealing of work by dielectric hysteresis. One example of a press such as may be used is the Thermatron sealing press manufactured by Radio Receptor, Inc., of New York, New York. The air cylinder for operating the head of the press is indicated at 157. The press is located for operation on jigs in the first series S1 at a station along the respective line of jigs and near the leading (left) end of the series S1. For this purpose, the table has a recess 159 near its left end as viewed in FIG. 5, and the press is located with its bed 153 in this recess flush with the top surface of the table. The head 155 of the press carries an electrode 161 which is of such width as to be adapted to contact two adjacent jigs 23 in series 51. It also carries an arm 163 which is adapted to engage the rearward end 107 of the toggle-breaking lever 101 to break the toggles of the two jigs in series S1 which are located to the left of the electrode 161 to open these two jigs as will be made clear.

The roll holder 155 is provided at the right end of the table for holding a roll R of flexible transparent electronically heat-sealable plastic film F. This holder may simply comprise a pair of brackets 167 secured to the table supporting an arbor 169 on which roll R is mounted. The width of the film corresponds to the height required for covers 19. The roll R is supported in line with series S1 of jigs 23, and the film F is adapted to be fed from the roll between pins 47, on the one hand, and pin 45, on the other hand, of each jig 23 in the series S1 of jigs.

Referring now to FIG. 16, there is shown a solenoid valve 171 for controlling both the air cylinder 119 (which may be referred to as the longitudinal feed cylinder) and the press cylinder 157, and a solenoid valve 173 for controlling the air cylinder 143 (which may be referred to as the cross-feed cylinder). Valve 171 is shown as having a compressed air inlet port 17 5, an exhaust port 177, and two transfer ports 179 and 181. Port 179 is connected to a T 183, from which a line 185 leads to the left end of longitudinal feed cylinder 119 and a line 187 leads to the lower end of the press cylinder 157. Line 185 is shown as including a speed valve 189 for throttling flow of air to the cylinder 119. Port 181 is connected to a T 191, from which a line 193 leads to the right end of cylinder 119 and a line 195 leads to the upper end of the press cylinder 157. When valve 171 is energized, compressed air is delivered via port 179 to the left end of cylinder 119 and the lower end of the press cylinder 157, and the right end of the cylinder 119 and the upper end of the press cylinder 157 are vented via port 181 and exhaust port 177 to accomplish raising of the head of the press and operation of pushers P1 and P2 through a forward stroke (i.e., toward the left for pusher P1, toward the right for pusher P2). Speed valve 189 delays the operation of the cylinder 119 so that the head of the press is raised before the pushers operate through a forward stroke. Conversely, when valve 171 is deenergized, compressed air is supplied via port 181 to the right end of cylinder 119 and the upper end of the press cylinder 157, and the left end of cylinder 119 and the lower end of the press cylinder are vented via port 179 and exhaust port 177 to accomplish lowering of the press head and operation of the pushers P1 and P2 through a return stroke. Speed valve 189 then prevents slamming of the pushers P1 and P2.

Valve 173 is shown as having a compressed air inlet port 196, an exhaust port 197 and a transfer port 198. Port 198 is connected by a line 199 to the right end of cross-feed cylinder 143. When valve 173 is energized, compressed air is delivered via port 198 and line 199 to the right end of the cylinder 143. When valve 173 is deenergized, the right end of cylinder 143 is vented via lin 199, port 198 and exhaust port 197.

A cross-feed limit switch 201 is mounted on rail 25 at the right end of table 21 in position for actuation by a jig 23 being pushed crosswise of the table by pusher P4 as this jig completes its crosswise movement and its end engages the rail 25. This switch 201 is a normally open switch. It is closed by a jig fed crosswise by pusher P4. A forward longitudinal feed limit switch 203 is mounted on stop 133 in position for actuation by the end jig at the right end of series S2 of jigs when series S2 is pushed toward the right (as viewed in FIG. 5) and the stated jig at the right end of series S2 completes its movement and engages stop 133. This switch is a normally closed switch. It is opened by the stated end jig on completion of the forward feed of series S2 (and S1). A cross-feed return limit switch 205 is mounted on the table in position for actuation by pusher P4 when this pusher P4 returns to its retracted position. This switch is a normally open switch. It opens when pusher P4 moves away from its retracted position and closes when pusher P4 returns to retracted position. A longitudinal feed return limit switch 207 is mounted on the table in position for actuation by pusher P1 when this pusher returns to its retracted position. This switch is a normally open switch. It closes when pusher P1 moves forward away from its retracted position and opens when pusher P1 returns to retracted position.

Electric power supply lines are indicated at L1 and L2 in FIG. 16. These are connected to the input terminals of a double-throw main control switch 209. One output terminal of switch 209 is connected by 'a line 211 to one terminal of a safety switch 213. This switch is a normally closed switch which is mounted on the press 151 for engagement by the clamping plate 55 of any jig in series 51 approaching the press 151 that should happen to be open. A line 215 extends from the other terminal of safety switch 213 to the input terminal, 217 of a. double-throw relay 219. The coil of relay 219 is indicated at 221. One output terminal of the relay is designated 223,and the other 225. When coil 221 is deenergized, the relay is closed across terminals 217 and 223. When the coil 221 is energized, the relay is closed across terminals 217 and 225. A line 227 including switch 207 extends from relay terminal 223 to one terminal of solenoid valve 173. A line 229 extends from the other terminal of valve 173 to the other output terminal of switch 209. Relay coil 221 is connected in series with switches 213 and 201 in a line 231 between lines 215 and 229. Solenoid valve 171 is connected in series with switches 203 and 205 in a line 233 between relay terminal 225 and line 229. Coil 221 is connected in parallel with valve 171 and switch 205 by means of a line 235.

Operation is as follows:

Operation of the apparatus is initiated by closing the main switch 209. With this switch closed, the ap- 7 paratus automatically cycles. Assuming that the apparatus starts with all four pushers P1, P2, P3 and P4 in their retracted position as illustrated in FIG. 14, normally open switches 205 and 207 will be closed (pushers P4 and P1 being retracted), normally open switch 201 will be open, and normally closed switch 203 will be held open by the jig at the right end of series S2 (see FIG. 16). With switch 201 open, relay coil 221 is deenergized, andrelay 219 is closed across terminals 217 and 223.. Accordingly, valve 173 is energized via line 211, switch 213' (which is normally closed), line 215, the relay 219., line 227, switch 207 (closed) and line 229. With valve 173 energized, air is delivered to the right end of'cross-feed cylinder '143' and cables 147 are thereupon pulled to actuate the pushers P3 and P4 through a forward stroke. Pusher P3 pushes the two jigs 23 at the leading (left) end of series S1 crosswise into position at the trailing (left) end of series S2 and pusher P4 pushes the two jigs at the leading (right) end of series S2 crosswise into position at the trailing (right) "end of series S1. This is permitted by reason of the fact that.

pushers P1 and P2 are in their retracted position illustrated in dotted lines in FIG. 5. As pusher P3 moves away from its retratced position, switch 205 opens, and switch 203 closes.

As the two jigs being pushed crosswise by pusher P4 approach the rail 25, one of these jigs engages switch 201, and this switch is closed as these two jigs complete their crosswise movement and engage the rail 25. When switch 201 closes, relay coil 221 is energized, the circuit therefor being completed via line 211, switch 213 (normally closed), line 231 and line 229. This operates the relay 219 to break the circuit across terminals 217 and 223, and close a circuit across terminals 217 and 225. This deenergizes valve 173, the right end of cross-feed cylinder 143 is vented, and spring means 149 thereupon returns pushers P3 and P4 to their retracted position. When pusher P4 returns to its retracted position, switch 205. is closed. With relay 219 closed across terminals 217 and 225 and. switch 205 closed, valve 171 is energized via line211, switch 213 (normally closed), line 215, relay 219, line 233 (including closed switches 203 and 205) and line 229. With valve 171 energized, air is supplied to the lower end of the press cylinder 157 and exhausted from the upper end of the press cylinder to raise the press. head 155. After the press head 155 rises, air is supplied to the left end of the longitudinal feed cylinder 119 and exhausted from its right end to cause pushers P1 and P2 to move through a forward stroke from their dottedline FIG. 5 position to their solid line FIG. 5 position. Accordingly, pusher P1 pushes series 81 of jigs forward (toward the left) and pusher P2 pushes series S2 of jigs forward (toward the right), During the forward feed, even though switch 201 may open, relay coil 221 is maintained energized via line 235. Also, on the forward feed, switch 207 opens. As the forward feed of the jigs in series S1 and S2 is completed, the forward jig in series S2 engages normally closed switch 203 and opens it. This deenergizes valve 171 and relay coil 221, the relay thereupon closing across terminals 217 and 223. With valve 171 deenergized, air

is supplied to the upper end of the press cylinder 157' and exhausted from its lower end to cause, the press head 155 to descend. Also, air is supplied to the right end of forward feed cylinder 119 and exhausted from its left end to cause pushers P1 and P2 to return to their retracted position shown in dotted lines in FIG. 5. When the pushers P1 and P2 return to their retracted position, normally open switch 207 is closed. Accordingly, valve 173 is energized and the cycle is repeated.

Thus, tracing the path of any one jig, and starting with this jig at the trailing (right) end of series S1, each time pusher P1 moves forward, the jig is moved forward (toward the left) two jig widths. Initially, the jig is open. Before it reaches the press 151, it will be closed as will under the electrode 161 on press head 155. Then the electrode 161 comes down on the jig, and rises. This step occurs during the dwell between successive advances of the series of jigs. Then the jig is advanced out of the press to the left of the press as viewed in FIG. 1. next time the press head descends, arm 163 on the press head engages the toggle-breaking lever 101 of the jig to cause it to open under the bias of jig spring 61. Subsequently, the jig is pushed crosswise by pusher P3 into position at the trailing (left) end of series S2. Then each time pusher P2 moves forward (toward the right),

the jig moves forward (to the right) two jig widths. Ultimately it is advanced to the leading (right) end of series S2, and finally is pushed crosswise by pusher P4 into position at the trailing end of series S1 to start another trip around. Thus, each jig is moved in steps through an endless rectangular path, passing through the press 151 and stopping under the head of the press in the course of its travel through this endless path.

FIG. 5 illustrates the apparatus with pushers P1 and P2 forward, and pushers P3 and P4 retracted. Accordingly, the jig 23 at the left end of series S1 (on the exit side of the press) is against the stop 131, and the jig at the right end of series S2 is against the stop 133. All the jigs in series S2 (which may be referred to as the return line of jigs) are open. Part of the jigs in series S1 (which may be referred to as the active line of jigs) from the jigat the right end of series S1 to. a jig on the right of the press 151 (on the entry side of the press) are open. From hereon to the press, the jigs in series S1 are closed. The two jigs shown immediately to the left of the press are shown closed. They will be opened the next time the press head descends. The two jigs at the extreme left end of series S1 are open. The plastic film F extends continuously from the roll R over the open jigs and through the closed jigs in series S1. A worker stationed at the table places blanks 3 in the open jigs 23 either in series S2 or at the trailing end of series S1. The flap or picture frame portion 9 of the blank is placed on the upper surfaces of the sides 35 and ends 37 and 39 of the lower electrode 33 on the base of the jig as shown in FIG. 11., The picture frame portion 9 is properly positioned by entry of pin 45 in hole 17 and by insertion of the edge of portion 9 opposite the fold 5 in the notches 49 in pins 47. 7 Card portion 7 of blank 3 extends upward from the picture frame. The plastic film F extends over the picture frame portion 9 of each blank 3 in the jigs in series S1. A worker stationed at the table places an article A on film F over the jig recess 41, as illustrated in FIG. 11. Then the clamping plate 55 of each jig is closed and locked by pushing down the toggle lever of the jig. When plate 55 is swung down, the card portion 7 of the blank is folded down on fold line 5 over the article and over the portion of the film F on the picture frame 9 as appears in FIG. 12. The slides 69 and ends 71 and 73 of the upper electrode 67 clamp the card, film and picture frame against the upper surfaces of the sides 35 and ends 37 'and 39 of lowerelectrode 33, and the film is stretched substantially taut over the article A. The latter is pushed down by the card into the recess 41 defined by electrode 33, as shown in FIG. 12. Accordingly, series S1 is made to include a number of closed jigs each including a blank 3, an article A and a portion of film F for entry into the press.

' When the jig is closed, the jig electrodes 33 and 67 are cold, i.e., at room temperature. Accordingly, the clamping of the work in the jig is effected without fusion (melting) of the film. In this respect, it will be understood that if the work were clamped between hot electrodes, the film wouldfuse, and the stretching of the filmwould cause it to rupture along the line of fusion. The clamping of the work prior to entry of the jig in the press avoids this.

As each closed jig in series S1 comes under the press head 155 and stops, the press head descends and elec- The trode 161 on the press head engages the clamping plate 55 of the jig. High frequency electrical energy is then applied to the bed 153, head 155 and electrode 161, and consequently to the electrodes 33 and 67 of the jig. This effects electronic heat sealing of the portion of the plastic film F in the jig to the card portion 7 and picture frame portion 9 of the cardboard blank 3 in the jig. Fusion of the film F over the zone under the edge of electrode 67 for sealing is accomplished without rupture of the film at the zone of fusion, even though the film is stretched taut over article A in the jig. The clamping of the work is maintained until the jig is moved off the bed of the press, allowing time for the fused plastic to solidify before the jig is opened, thereby completely avoiding rupture. The completed packages 1 come out of the opened jigs at the left end of series S1 in a connected together succession, the film F still being continuous. Ultimately, the individual packages may be separated -by slitting the tfilm between packages. To enable the jigs to be transferred by pusher P3 from series S1 to series S2, the joined-together succession of packages is lifted above the pins 45 and 47, and this clears the two jigs at the left end of series S1 for oross-feeding over to series S2.

It will be understood that the'above described method of this invention may be used for producing skin packages of types other than the picture frame package 1. For example, the method may be used for producing skin packages wherein an article (or articles) is packaged on a card without a picture frame such as the frame 9 of package 1, as shown by above-mentioned application Serial No. 7 46,892.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above methods without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. The method of packaging an article on a card hav ing a flap joined thereto along a fold, said flap having a window opening therein, said card and flap having a coating of an electronically heat-scalable synthetic plastic on one face thereof, comprising the steps of applying the flap coated face up over an electrode having a recess therein, the window opening in the flap registering with said recess, applying a film of flexible transparent electronically heatsealable synthetic plastic over said flap, applying an article to the film above said window opening and recess, folding the card coated face down over the article, applying a second electrode to the card and pressing to clamp together the margin of the card, the film and the flap around the recess and concomitantly to stretch the film substantially taut over the article, the article and the portion of the film stretched over the article projecting down through the window opening in the fiap and being accommodated in said recess, and applying high frequency electrical energy to the electrodes to eifect electronic sealing of the coating on the card and flap and the film around the article with the margin of the card, the film and the flap clamped between said electrodes.

2. The method of packing articles on cards comprising intermittently advancing a line of jigs through an electronic heat-sealing press, each jig comprising a lower electrode and an upper electrode adapted to be opened and closed, the lower electrode having a recess therein, withdrawing a strip of flexible transparent electronically heatsealable film from a supply thereof concomitantly with the advance of the line of jigs, said strip extending throughout the length of said line of jigs overlying the recesses in the lower electrodes of the jigs, placing an article on the strip over the recess of each jig on its way to the press, applying a card over the article in each jig, said card being electronically heat-scalable on its downward face, closing the upper electrode-of each jig on its way to the press to clamp together the margin of the card and the portion of the strip in the jig all around the article and thereby stretching the strip substantially taut over the article, the article and the portion of the strip stretched over the article being accommodated in the recess in the lower electrode, and, as each jig comes into the press and stops therein, operating the press to apply hi h frequency electrical energy to said electrodes to etfect electronic heat-sealing of the strip to the card in the jig all around the article therein.

3. The method of packing articles on cards, each having a flap joined thereto along a fold, the flap having a window opening, the card and flap having a coating of an electronically heat-scalable synthetic plastic on one face thereof, comprising intermittently advancing a line of jigs through an electronic heat-sealing press, each jig comprising a lower electrode and an upper electrode adapted to be opened and closed, the lower electrode having a recess therein, withdrawing a strip of flexible transparent electronically heat-scalable film from a supply thereof concomitantly with the advance of the line of jigs, said strip extending throughout the length of said line of jigs overlying the recesses in the lower electrodes of the jigs, applying the flap of a card to the lower electrode of each jig underneath the strip, the coated face of the flap being uppermost, the window opening in the fiap registering with the recess in the lower electrode, placing an article on the strip over the recess of each jig on its way to the press, closing the upper electrode of each jig on its way to the press to fold the card down on the strip and to clamp together the margin of the card, the portion of the strip and the flap in the jig all around the article and thereby stretching the strip substantially taut over the article, the article and the portion of the strip stretched over the article projecting down through the window opening in the flap and being accommodated in the recess in the lower electrode, and, as each jig comes into the press and stops therein, operating the press to apply high frequency electrical energy to said electrodes to effect electronic heat-sealing of the strip to the card and flap in the jig all around the article therein.

4. The method of packing articles on cards comprising intermittently advancing a line of jigs through an electronic heat-sealing press, said cards being electronically heat-scalable on at least one face thereof, each jig comprising a lower electrode and an upper electrode adapted to be opened and closed, one of said electrodes having a recess therein, withdrawing a strip of flexible transparent electronically heat-scalable film from a supply thereof concomitantly with the advance of the line of jigs, said strip extending throughout the length of said line of jigs overlying the lower electrodes of the jigs, positioning a card and an article in each jig with the article between said card and said strip, said electronically heat-sealable face of said card being adjacent said article, closing the upper electrode of each jig on its way to the press to clamp together the margin of the card and the portion of the strip in the jig all around the article and thereby stretching the strip substantially taut over the article, the article and the portion of the strip stretched over the aricle being accommodated in the recess in said one electrode and, as each jig comes into the press and stops therein, operating the press to apply high frequency electronic energy to said electrodes to effect electronic heat-sealing of the strip to the card in the jig all aroundthe article therein.

5. The method of packing articles on cards comprising intermittently advancing a line of jigs through an electronic heat-sealing press, said cards being adapted for electronic heat-sealing of an electronically heat-scalable film to one face thereof, each jig comprising a lower electrode and an upper electrode adapted to be opened and closed, one of said electrodes having a recess therein, withdrawing a strip of flexible transparent electronically heat-sealable film from a supply thereofi concomitantly with the advance of the line of jigs, said strip extending throughout the length of said line of jigs overlying the lower electrodes of the jigs, positioning a card and an article in each jig with the article between said card and said strip, said face of said card being adjacent said article, closing the upper electrode of each jig on its way to the press to clamp together the margin of the card and the portion of the strip in the jig all around the article and thereby stretching the strip substantially taut over the article, the article and the portion of the strip stretched over the article being accommodated in the re cess in said one electrode and, as each jig comes into the press and stops therein, operating the press to apply high frequency electronic energy to said electrodes to effect electronic heat-sealing of the strip to the card in the jig all' around the article therein.

References Cited in the file of thispatent UNITED STATES PATENTS 2,855,735 Groth Oct. 14,1958 2,879,635 Brock Mar. 31, 1959 2,927,409 Heyer Mar. 8, 1960 2,958,168 Vogt Nov. 1, 1960 2,991,600 Lancaster July 11, 1961 3,030,752 De Woskin Apr. 24, 1962 OTHER REFERENCES 

1. THE METHOD OF PACKAGING AN ARTICLE ON A CARD HAVING A FLAP JOINED THERETO ALONG A FOLD, SAID FLAP HAVING A WINDOW OPENING THEREIN, SAID CARD AND FLAP HAVING A COATING OF AN ELECTRONICALLY HEAT-SEALABLE SYNTHETIC PLASTIC ON ONE FACE THEREOF, COMPRISING THE STEPS OF APPLYING THE FLAP COATED FACE UP OVER AN ELECTRODE HAVING A RECESS THEREIN, THE WINDOW OPENING IN THE FLAP REGISTERING WITH SAID RECESS, APPLYING A FILM OF FLEXIBLE TRANSPARENT ELECTRONICALLY HEATSEALABLE SYNTHETIC PLASTIC OVER SAID FLAP, APPLYING AN ARTICLE TO THE FILM ABOVE SAID WINDOW OPENING AND RECESS, FOLDING THE CARD COATED FACE DOWN OVER THE ARTICLE, APPLYING A SECOND ELECTRODE TO THE CARD AND PRESSING TO CLAMP TOGETHER THE MARGIN OF THE CARD, THE FILM AND THE FLAP AROUND THE RECESS AND CONCOMITANTLY TO STRETCH THE FILM SUBSTANTIALLY TAUT OVER THE ARTICLE, THE ARTICLE AND THE PORTION OF THE FILM STRETCHED OVER THE ARTICLE PROJECTING DOWN THROUGH THE WINDOW OPENING IN THE FLAP AND BEING ACCOMMODATED IN SAID RECESS, AND APPLYING HIGH FREQUENCY ELECTRICAL ENERGY TO THE ELECTRODES TO EFFECT ELECTRONIC SEALING OF THE COATING ON THE CARD AND FLAP AND THE FILM AROUND THE ARTICLE WITH THE MARGIN OF THE CARD, THE FILM AND THE FLAP CLAMPED BETWEEN SAID ELECTRODES. 